JP2000169400A - Production of styrene trimer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an advantageous production method of 1,3,5- triphenylcyclohexane. SOLUTION: This production method comprises (i) a step for condensing phenyl styryl ketone with acetone under a basic condition to provide 3,5- diphenyl-2-cyclohexen-1-one, (ii) a step for allowing a phenyl Grignard reagent to act on the obtained 3,5-diphenyl-2-cyclohexen-1-one to provide 1,3,5-triphenyl-2- cyclohexen-1-one, (iii) a step for subjecting the obtained 1,3,5-triphenyl-2- cyclohexen-1-one to a dehydration reaction and the catalytic reduction reaction to provide the objective 1,3,5-triphenylcyclohexane.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing 1,3,5-triphenylcyclohexane.

[0002]

2. Description of the Related Art Polystyrene is widely used for food trays and containers. However, there is a concern that styrene oligomers may elute when hot water is placed in a polystyrene container. Various studies have been made on what kind of styrene oligomers are eluted and how safe the styrene oligomers are.

[0003]

By the way, there are various substances in the above-mentioned styrene oligomer, and if a sample of each can be obtained, it will be easy to analyze it. Therefore, a method for producing the sample is required. ing.

[0004]

According to the present invention, among these styrene oligomers, in particular, a styrene trimer,

Embedded image And a simple method for producing 1,3,5-triphenylcyclohexane represented by the following formula:

Embedded image Is condensed under basic conditions with phenylstyryl ketone represented by

Embedded image 3,5-diphenyl-2-cyclohexene-
1-one, (ii) the resulting 3,5-diphenyl-
By reacting 2-cyclohexen-1-one with a phenyl Grignard reagent,

Embedded image 1,3,5-triphenyl-2-cyclohexen-1-ol represented by the following formula (iii):
1,3,5- by subjecting triphenyl-2-cyclohexen-1-ol to a dehydration reaction and a catalytic reduction reaction
This is a method for producing triphenylcyclohexane.

[0005]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The dehydration reaction and the catalytic reduction reaction of the above (iii) are usually carried out by the following (iii-1) or (iii-
This is performed by the step 2). That is, (iii-1) the obtained 1,3,5-triphenyl-2-cyclohexene-
1-ol is subjected to a dehydration reaction to give 5

Embedded image To 1,3,5-triphenyl-1,3-cyclohexadiene and then catalytically reducing 1,3,5-triphenyl-1,3-cyclohexadiene, or (iii-2) 1,3,5-triphenyl-2
-Catalyzed reduction of cyclohexen-1-ol to give

Embedded image Is obtained, and the obtained 1,3,5-triphenyl-1-cyclohexanol is subjected to a dehydration reaction to obtain 1,3,5-triphenyl-1-cyclohexanol.

Embedded image 1,3,5-triphenyl-1-cyclohexene represented by, and 1,3,5-triphenyl-1-cyclohexene is catalytically reduced to produce 1,3,5-triphenylcyclohexane. That is.

In the present invention, 3,5-diphenyl-2
Step (i) for obtaining -cyclohexen-1-one
Is carried out by condensing phenylstyryl ketone and acetone under basic conditions. Examples of the base used include sodium methoxide, sodium ethoxide, alkali metal alkoxides such as potassium tert-butoxide, and sodium hydride. And alkali metal hydroxides such as sodium hydroxide and potassium hydroxide. The condensation reaction is usually carried out
The reaction is performed in a solvent, and examples of the solvent used include alcohols such as methanol and ethanol, tetrahydrofuran,
Ethers such as diethyl ether are mentioned, but it is preferable to use acetone in excess as a reaction solvent. The reaction temperature is usually in the range of 20 to 70 ° C, and the reaction time is usually about 10 minutes to 24 hours. After completion of the reaction, the reaction solution is subjected to a usual post-treatment, for example, water is added to the reaction solution, and the mixture is extracted with an organic solvent.

In the step (ii) for obtaining 1,3,5-triphenyl-2-cyclohexen-1-ol,
The reaction is carried out by reacting 5-diphenyl-2-cyclohexen-1-one with a phenyl Grignard reagent. The phenyl Grignard reagent is prepared from a halogenated benzene such as bromobenzene or iodobenzene and magnesium by a conventional method. A phenyl Grignard reagent commercially available as a phenylmagnesium chloride solution in tetrahydrofuran, a phenylmagnesium bromide solution in diethyl ether, or a phenylmagnesium bromide solution in tetrahydrofuran can also be used. 3,5-diphenyl-2-cyclohexene-1-
The reaction between the on and the phenyl Grignard reagent is usually carried out in an ether such as tetrahydrofuran and diethyl ether.
The reaction is performed in the presence of a copper (I) salt such as copper (I) chloride. The amount of the reagent used is usually 0.9 to 2.0 moles of the phenyl Grignard reagent and the copper (I) salt, respectively, based on 1 mole of 3,5-diphenyl-2-cyclohexen-1-one. It is about 0.01 to 0.2 mol. The reaction temperature is usually in the range of 0 to 50 ° C., and the reaction time is usually 10
Minutes to 24 hours. After completion of the reaction, the reaction solution is subjected to a usual post-treatment, for example, water or an acid such as hydrochloric acid is added to the reaction solution, and the mixture is extracted with an organic solvent.

[0008] 1,3,5- in step (iii-1)
1,3,5-Triphenyl-2-cyclohexene-1 for obtaining triphenyl-1,3-cyclohexadiene
-Dehydration reaction of all, usually, phosphorus pentoxide 1,3,
It is carried out by acting on 5-triphenyl-2-cyclohexen-1-ol. The reaction is usually performed in an organic solvent, and examples of the organic solvent used include benzene, toluene, aromatic hydrocarbons such as xylene, pentane, and aliphatic hydrocarbons such as hexane.
The molar ratio of 3,5-triphenyl-2-cyclohexen-1-ol to diphosphorus pentoxide is usually 1:
It is about 1 to 1:10. The reaction temperature is usually 20
In the range of ３０50 ° C., the reaction time is usually about 30 minutes to 24 hours. After completion of the reaction, usual post-treatments, for example, operations such as removal of solid impurities by filtration, addition of water to the reaction solution and extraction with an organic solvent, removal of the solvent under reduced pressure, etc., and purification by chromatography or the like as necessary.

In the catalytic reduction reaction of 1,3,5-triphenyl-1,3-cyclohexadiene, hydrogenation is carried out according to a conventional method in the presence of a metal catalyst. Examples of the metal catalyst include palladium, platinum, nickel, and the like. Preferred examples of the metal catalyst include palladium held on activated carbon. The reaction is usually performed in an alcohol such as methanol or ethanol. The reaction temperature is usually 20 to
In the range of 50 ° C., the reaction time is usually about 30 minutes to 24 hours. After completion of the reaction, usual post-treatments, for example, operations such as removal of solid impurities by filtration, addition of water to the reaction solution and extraction with an organic solvent, removal of the solvent under reduced pressure, etc., and purification by chromatography or the like as necessary.

In the step (iii-2), 1,3,5-
The catalytic reduction of triphenyl-2-cyclohexen-1-ol and the catalytic reduction of 1,3,5-triphenyl-1-cyclohexene are also performed by the above-mentioned 1,3,5-triphenyl-ol.
It can be carried out under the same reaction conditions as the catalytic reduction of 1,3-cyclohexadiene. Also, 1,3,5-triphenyl-1
The dehydration reaction of -cyclohexanol is generally performed using diphosphorus pentoxide, as in the dehydration reaction of 1,3,5-triphenyl-2-cyclohexen-1-ol. The reaction is also generally performed in an organic solvent, and examples of the organic solvent used include aromatic hydrocarbons such as benzene, toluene, and xylene, pentane, and aliphatic hydrocarbons such as hexane. The molar ratio of 5-triphenyl-2-cyclohexen-1-ol to diphosphorus pentoxide is usually about 1: 1 to 1:10 in terms of molar ratio. Also,
The reaction temperature is usually in the range of 20 to 50 ° C, and the reaction time is usually about 30 minutes to 24 hours. After completion of the reaction, usual post-treatments, for example, operations such as removal of solid impurities by filtration, addition of water to the reaction solution and extraction with an organic solvent, removal of the solvent under reduced pressure, etc., and purification by chromatography or the like as necessary. The product in each of the above-mentioned steps can be subjected to the next step as a solution without isolation and purification.

There are several stereoisomers in 1,3,5-triphenylcyclohexane. According to the above-mentioned step (iii-1), a mixture of isomers rich in 1e, 3e, 5e isomers is obtained. On the other hand, according to the step (iii-2), a mixture of isomers enriched in 1e, 3e, 5a isomers is obtained, so that the method of the present invention can also be used for production of specific isomers. .

[0012]

The present invention will be described below in more detail with reference to examples. Example 1 (3,5-diphenyl-2-cyclohexene-
Production of 1-one) 50.0 g of phenylstyryl ketone was added to 200 m of acetone.
1 sodium methoxide
3.3 g was added and heated to 40-50 ° C. Two hours later,
Water was added to the residue obtained by evaporating the solvent under reduced pressure, and the mixture was extracted with diethyl ether. Water, saturated saline,
After sequentially washing with water and drying over anhydrous sodium sulfate, the solvent is distilled off under reduced pressure, and the residue is subjected to silica gel column chromatography (elution solvent: hexane / ethyl acetate (4/1, v / v), then Toluene, hexane / ethyl acetate (7/3, v / v)), 3,5-diphenyl-2
33.3 g of -cyclohexen-1-one were obtained.

Example 2 (1,3,5-triphenyl-2)
-Production of cyclohexen-1-ol) Copper chloride 1.4 was added to 120 ml of a diethyl ether solution containing 121 mmol of phenylmagnesium bromide under ice cooling.
0 g was added and stirred for 30 minutes. To this, a solution of 15.0 g of 3,5-diphenyl-2-cyclohexen-1-one in 90 ml of anhydrous benzene was added dropwise over 30 minutes, and the mixture was kept under ice cooling for another 2 hours. Then, water was added, and the mixture was adjusted to pH 1 by adding concentrated hydrochloric acid and extracted with diethyl ether. The ether solution was washed successively with water and saturated brine, dried over anhydrous sodium sulfate, the solvent was distilled off under reduced pressure, and the residue was subjected to silica gel column chromatography (eluting solvent: toluene) to give 1,3,5 -11.4 g of triphenyl-2-cyclohexen-1-ol were obtained.

Example 3 (1,3,5-triphenyl-
Production of 1,3-cyclohexadiene) 1,3,5-triphenyl-2-cyclohexene-1-
Dissolve 11.4 g of all in 200 ml of toluene, add 45.9 g of diphosphorus pentoxide over about 10 to 15 minutes with stirring at room temperature, further stir at room temperature for 1.5 hours, and then filter to remove solids. Removal, the solvent was distilled off under reduced pressure, and the residue was subjected to silica gel column chromatography (elution solvent: hexane), and the obtained product was recrystallized from ethanol to give 1,3,5-triphenyl-1,1
6.32 g of 3-cyclohexadiene was obtained.

Example 4 (Production of 1,3,5-triphenylcyclohexane) 7.00 g of 1,3,5-triphenyl-1,3-cyclohexadiene was mixed with ethyl acetate / ethanol (1/1, v / v).
v) Dissolve in 100 ml of mixed solvent, and add 10% Pd / C1.
5 g was added, and the mixture was kept at room temperature for 10 hours to perform catalytic reduction. Then, the solid content was removed by filtration, the solvent was distilled off under reduced pressure, and the residue was subjected to silica gel column chromatography (elution solvent: hexane, then toluene) to give 1,3,3.
5.75 g of 5-triphenylcyclohexane (1e, 3e, 5e form / 1e, 3e, 5a form = 5.7 / 1) was obtained.

Example 5 (1,3,5-triphenyl-1)
-Production of cyclohexanol) 1,3,5-triphenyl-2-cyclohexene-1-
1.20 g of all were dissolved in 40 ml of ethanol, and 10
% Pd / C (200 mg) was added thereto, and the mixture was kept at room temperature for 3 hours to perform catalytic reduction. Next, the solid content was removed by filtration, and the solvent was distilled off under reduced pressure to obtain 1.20 g of 1,3,5-triphenyl-1-cyclohexanol.

Example 6 (1,3,5-triphenyl-1)
-Production of cyclohexene) 1.20 g of 1,3,5-triphenyl-1-cyclohexanol was dissolved in 50 ml of toluene, 8.00 g of diphosphorus pentoxide was added, the mixture was stirred at room temperature for 1.5 hours, and then filtered. The solid was removed, the solvent was distilled off under reduced pressure, and the residue obtained was subjected to silica gel column chromatography (elution solvent: hexane) to obtain 1.15 g of 1,3,5-triphenyl-1-cyclohexene. .

Example 7 (Production of 1,3,5-triphenylcyclohexane) 1,3,5-triphenyl-1-cyclohexene 1.1
5 g is dissolved in 50 ml of ethanol, and 10% Pd / C2
After adding 00 mg and keeping the mixture at room temperature for 3 hours, catalytic reduction was performed. Then, the solid content was removed by filtration, and the solvent was distilled off under reduced pressure to remove 1,3,5-triphenylcyclohexane (1.
e, 3e, 5e body / 1e, 3e, 5a body = 1/4) 1.
10 g were obtained.

[0019]

According to the present invention, 2,4,6-triphenylcyclohexane can be easily produced.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (reference) // C07B 61/00 300 C07B 61/00 300 F term (reference) 4H006 AA02 AC11 AC28 BA69 BD70 4H039 CA40 CB10 CH10

Claims (3)

[Claims] (1) A method of condensing phenylstyryl ketone and acetone under basic conditions to give 3,5-
Diphenyl-2-cyclohexen-1-one was obtained, (i
i) reacting the obtained 3,5-diphenyl-2-cyclohexen-1-one with a phenyl Grignard reagent to give 1,3,5-triphenyl-2-cyclohexene-1-one;
1,3,5-triphenylcyclohexane characterized by subjecting (1, iii) the obtained 1,3,5-triphenyl-2-cyclohexen-1-ol to a dehydration reaction and a catalytic reduction reaction. Manufacturing method. (I) condensing phenylstyryl ketone and acetone under basic conditions to give 3,5-
Diphenyl-2-cyclohexen-1-one was obtained, (i
i) reacting the obtained 3,5-diphenyl-2-cyclohexen-1-one with a phenyl Grignard reagent to give 1,3,5-triphenyl-2-cyclohexene-1-one;
And (iii-1) the resulting 1,3,5-triphenyl-2-cyclohexen-1-ol was subjected to a dehydration reaction to lead to 1,3,5-triphenyl-1,3-cyclohexadiene. And then 1,3,5-triphenyl-
A method for producing 1,3,5-triphenylcyclohexane, comprising catalytically reducing 1,3-cyclohexadiene. (3) Condensation of phenylstyryl ketone and acetone under basic conditions to give 3,5-
Diphenyl-2-cyclohexen-1-one was obtained, (i
i) reacting the obtained 3,5-diphenyl-2-cyclohexen-1-one with a phenyl Grignard reagent to give 1,3,5-triphenyl-2-cyclohexene-1-one;
And (iii-2) catalytically reducing the obtained 1,3,5-triphenyl-2-cyclohexen-1-ol to obtain 1,3,5-triphenyl-1-cyclohexanol, 1,3,5-triphenyl obtained
1-cyclohexanol is subjected to a dehydration reaction to give 1,3,5-
Led to triphenyl-1-cyclohexene,
A method for producing 1,3,5-triphenylcyclohexane, comprising catalytically reducing 3,5-triphenyl-1-cyclohexene.